Mix pudding according to package directions. After pudding is set, add Cool Whip. In large bowl, start with layer of wafers or cake. Next a layer of pudding, followed by a layer of bananas. Continue layering process until bowl is full and ending with a layer of pudding. Refrigerate until ready to serve. (Some add low fat sour cream to the pudding mix, but without sugar, it does make the pudding tart.).